EP2225795B1 - Antenna field for a motor vehicle disk - Google Patents

Abstract

An improved antenna field has at least one capacitance switched between one of the two bus bars. At least one center section of the heating wire is formed between 20% and 80% of the total length of the heating wire, and/or at least one capacitance is switched between at least two center sections of the heating wires formed between 20% and 80% of the total length of two heating wires. The at least one capacitance is greater than 50 pF.

Description

The invention relates to an antenna field for a motor vehicle window, in particular a motor vehicle rear window according to the preamble of claim 1.

It is well known that, for example, provided in the rear window of a passenger car heating panel can also be used as an antenna array. Usually, a bus bar is provided in the rectangular or trapezoidally shaped rear window on the left and right sides, between which run in the direction parallel to each other, the individual heating wires. Each of the two busbars is connected to the pole of a vehicle battery.

On equipotential lines transverse secondary conductors can be provided which are fundamentally suitable for improving the reception qualities of such a rear window antenna. Since these secondary conductors extend on the aforementioned equipotential lines, it is essentially ensured that no cross-currents flow here between the heating wires.

Such, serving as an antenna field rear window heater may comprise a heating field or more heating fields. It is also possible that in addition to the heating field, a separate or additional antenna array is provided. Even if only one antenna field completely separate from the heating field were provided in a pane, in particular in the rear window of the motor vehicle, the adjacent heating field would have repercussions on the antenna field, i. ultimately affect the reception quality of the antenna field with.

The housed in the rear windows antenna and / or heating panels are often used for radio reception, especially the reception of radio and TV programs in the LW, MW, KW, FM and / or microwave range.

Corresponding heating and / or antenna fields are for example from the DE 100 33 336 A1 , of the DE 43 21 805 A1 , of the EP 1 366 540 B1 as well as the DE 43 23 239 C2 known. Here, for example, from the aforementioned DE 100 33 336 A1 It can also be seen that, in an embodiment variant according to FIG. 6, a capacitance is additionally connected between the two busbars.

From the DE 195 41 083 A1 is to take a glass pane for a rear window as known, the heater also serves as an antenna system. According to this prior publication is proposed as a solution to create a glass antenna, which ensures a better view of the driver to the rear. The antenna itself comprises a plurality of substantially horizontally oriented and parallel with offset heating wires, which from a left to a right busbar run. In the middle extending transversely to a middle equipotential line, a conductor wire is provided, which connects the plurality of transverse thereto heating wires electrically-galvanically. Finally, another shorter conductor wire is arranged parallel to the top heating wire, which results in a capacitive coupling to the adjacent heating wire. The antenna pickup then takes place via this conductor wire. According to this prior publication, the capacity should be less than 40 pF, since otherwise it would be nonsensical to increase the coupling capacity beyond 40 pF.

The DE 195 41 083 A1 describes in the context of an embodiment that a vertically extending to the horizontally extending Scheibenheizdrähte conductor wire is additionally provided. Separated from this, a vertical conductor wire is also provided in the lower heating field, which is capacitively coupled to the vertical conductor wire provided in the upper heating field via a capacitor, which, however, is formed only by the heating wires themselves.

A vehicle antenna is further from the DE 44 47 134 A1 to be known as known. Also in this prior publication heating and antenna fields are described, which are basically U-shaped, ie, for example, on the right edge of the disc in two linear extension to each other and separate busbars comprise, starting from which, in parallel position heating wires extend to an opposite common busbar. In some embodiments, a special film-like conductor is attached to the window above the actual heating field, and although on the inner surface of the windowpane. As a result, a slot antenna can be formed between the body and the film-like conductor.

In order to connect these film-type conductors to the remaining heating and antenna field for picking up the signals (with an inner conductor of a coaxial cable connected to the film-type conductor), a capacitor for bridging between the film-type conductor and the one bus bar is used. This causes a galvanic isolation to the heating field, although at the same time the RF antenna signals can be forwarded via the film-like conductor to the inner conductor of the coaxial cable. For this capacitor arranged in the antenna feed line between a separate antenna structure in the form of the film-type conductor and the heating field, the capacitance values z. B. 100 pF, for example, to transmit the FM frequencies in the antenna port.

The object of the present invention, in contrast, is to provide an improved antenna panel integrated in a pane which consists wholly or partly of the heating field or comprises it and / or is provided as separate separate or additional antenna field next to the heating field.

The object is achieved according to the features specified in claim 1. Advantageous embodiments of the invention are specified in the subclaims.

In the context of the invention are now based on completely new design-Gebungen respect to the heating field corresponding Adaptation measures to improve the reception quality of an integrated in the disc antenna array provided. However, the advantages according to the invention arise not only when the entire heating field is also used as an antenna field, but above all even if the heating field is split into several heating fields, individual heating fields, for example, serve as an antenna field or even one of the one or several heating fields remote pure antenna field is provided.

In the present invention, it is assumed that a busbar structure in which the busbars are provided on one or at least two non-opposite sides of the disc, usually on the lower, usually more or less horizontally extending side of the window. It should also be possible within the scope of the invention that the two busbars are wholly or substantially not provided on opposite sides of a window or a window, so for example wholly or partially on the underside of a window and wholly or partly on a right or left side of the automobile window.

In such an embodiment (although also in conventional embodiments with busbars provided in the motor vehicle windows on opposite sides), an improvement of the antenna characteristic, in particular of the reception quality, is realized in that a busbar and a rather middle section of a heating wire (the mean distance should be between 20% and 80% of the total length of a corresponding heating wire) means connected to a capacity.

In addition, such a capacitance can also be connected between two heating wires connected to the respective busbars, namely preferably between a middle section of two corresponding heating wires, wherein the middle section of the two heating wires should again preferably be between 20% and 80% of the total length of the relevant heating wire ,

Likewise, it can additionally be provided that a capacitance is additionally connected directly between the two busbars.

The mentioned capacities, i. the at least one capacitance in each case should be connected and / or provided as far as possible in a direct connection between the relevant connection points on the busbar sections and / or the preferably central sections of the mentioned heating wires, since preferably in addition to the capacitance other components as well, e.g. an inductance may be provided to produce a series resonant circuit.

Preferably, this capacity is still provided at the level of the disc material. Preferably, the capacity is realized in the form of a discrete or concentrated component.

The at least one capacitance can be soldered via wires, for example, as an electrolytic capacitor (ELKO capacitance). Also suitable are ceramic capacitors, flexible printed circuit boards etc.

A favorable order of magnitude for the capacity is, for example, between 50 pF and 10 μF. Frequently values above 0.1 nF or above 0.1 μF and in particular above 0.5 nF or above 0.5 μF will suffice for FM reception.

Basically, the capacitive coupling can also be realized by a plurality of capacitors connected in series or, for example, by a series resonant circuit of capacitor and coil, etc. In this case, a center tap between two capacitors connected in series, which is directly or e.g. is grounded via a throttle (in particular to body ground). However, connecting multiple capacitances above ground would adversely affect antenna characteristics and reception qualities.

In summary, it can be stated that antenna properties can be realized by the solution according to the invention, which have a lower frequency dependence, i.e. a lower frequency dependence, than a comparable antenna and heating field. So have a larger bandwidth. In addition, can be realized in the invention, a suppression or shift of the resonance behavior of the heating element for high-frequency signals.

The invention is particularly suitable for new geometries for heating panels. The invention therefore has particular advantages when heating fields are used, which comprise, for example, trapezoidal spaced apart or even after concentric circles or ovals, etc. formed heat conductor. In principle, the heating conductors should have a similar overall length (so that an approximately comparable thickness of the Heating conductor results - to produce comparable total resistance per heating wire), can be thought in a formed from concentric circles in a similar arrangement heating field, to connect inside heating conductor at one end to produce a total of longer heating conductors. In this case, at least one capacitance can also be switched directly at the corresponding points to one of the busbars and / or also between the heat conductors with each other or between a heat conductor and a busbar, which contribute to similar improvements of the antenna field, as described above with reference to FIGS Busbar switched capacity was explained. This is particularly important when due to the interconnection of conductors for the production of heaters with greater overall length, no lying on equipotential surfaces secondary conductors are switchable.

Figur 1 :

ein erstes schematisches, nicht zur Erfin- dung gehörendes Ausführungsbeispiel eines Heiz- und Antennenfeldes, welches in einer Scheibe eines Kraftfahrzeuges integriert ist;

Figur 2 :

ein erfindungsgemäßes Ausführungsbeispiel, bei welchem zwei Heizleiter über eine Ver- bindungsleitung zusammengeschaltet sind, wobei zwischen der Verbindungsleitung und einer Sammelschiene ein Kondensator vor- gesehen ist;

Figur 3 :

ein weiteres abgewandeltes erfindungsgemä- ßes Ausführungsbeispiel, bei welchem die Sammelschienen an zwei nicht gegenüberlie- genden Seiten einer Heckscheibe vorgesehen sind; und

Figur 4 :

ein zu Figur 2 geringfügig abgewandeltes, weiteres erfindungsgemäßes Ausführungsbei- spiel mit einer zusätzlichen kapazitiven Verbindung zwischen zwei Heizleitern, die jeweils an den entsprechenden beiden Sam- melschienen angeschlossen sind.

Further advantages, details and features of the invention will become apparent from the embodiment illustrated with reference to drawings. In detail:

FIG. 1:

a first schematic, not belonging to the invention embodiment of a heating and antenna field, which is integrated in a disc of a motor vehicle;

FIG. 2:

an inventive embodiment in which two heating conductors are interconnected via a connection line, wherein between the connecting line and a bus is provided with a capacitor;

FIG. 3:

a further modified embodiment according to the invention, in which the busbars are provided on two non-opposite sides of a rear window; and

FIG. 4:

one too FIG. 2 slightly modified, further embodiment according to the invention with an additional capacitive connection between two heating conductors, which are each connected to the corresponding two busbars.

In FIG. 1 is a schematic front view of a disc 1, for example, a motor vehicle, in particular a rear window 1 'indicated that in schematic view an upper boundary or boundary edge 1a, a lower boundary or boundary edge 1b and a left and a right boundary or boundary edge 1c and 1d , In practice, these boundary edges are not in pairs parallel to each other, but curved, more approximate to a trapezoidal shape or the like, since the windows are usually wider from top to bottom. Restrictions on the shape of the discs are so far not given, so that even any curved boundary lines are conceivable.

In the disk thus formed, a heating field 7 is integrated, which comprises a plurality of outside or inside the disk extending conductors 9, which in the shown Embodiment after FIG. 1 between a first and a second busbar 11, in the illustrated embodiment between the left busbar 11a and a subsequent right busbar 11b extend. The heating field 7 forms in the embodiment FIG. 1 an antenna field 5.

Each busbar is associated with a supply or connecting line 13a or 13b, wherein, for example, the connection line 13a is connected to the battery supply network on board the motor vehicle (usually the positive pole) and the other supply line 13b to the other pole, for example the body ground. In the connection or supply lines are usually blocking circuits to prevent flow of high-frequency currents.

In the illustrated embodiment, the individual conductors 9 are provided extending in a more or less equidistant arrangement between the busbars due to the selected geometry for the heating field, with an always constant distance is not mandatory or at least not over the entire length of the individual heating element is necessary. In this case, the geometry is selected such that the two busbars 11a and 11b are provided on one side of the disk, in the embodiment shown in the region of the lower boundary 1b, wherein the busbars are arranged symmetrically to a central plane of symmetry 14. In FIG. The heat conductors 9 are for example partially circular or even semicircular in the illustrated embodiment, but may also have other waveforms, here semi-oval, etc., wherein the radii or diameter from inside to outside are increasingly larger, so that the length of the individual heating increases from the inside out.

Furthermore, a secondary line 15 is provided, which connects the outer eight heating conductors in the middle and serves as Antennenabgriffsleitung 17. Such a secondary line 15 is galvanically considered on equipotential surfaces, whereby the DC distribution of the heating field is not changed. Nevertheless, this improves the antenna receiving characteristic, which is well known. Furthermore, two further Antennenabgriffsleitungen 117 are connected to the respective opposite outer ends of the two busbars 11a and 11b, but which may also be connected elsewhere in the busbar or the heating field, possibly even with the feed lines 13a or 13b may coincide.

Thus, in the exemplary embodiment shown, two heating field connections 13a and 13b and three antenna tapping connections 17, 117 are provided. But the number of connections can also be different, especially if, for example split heat fields are provided, which not only run between two busbars (for example, known from the DE 100 33 336 A1 or the DE 43 21 805 A1 ).

In the embodiment shown, the two bus bars 11 are further provided lying in a horizontal line, in axial extension to each other (even if the disc top view may be curved), wherein the two busbars at its inner end 11'a and 11'b via a interconnected capacitance 19 are interconnected.

There is thus a direct connection between the two busbars 11a and 11b with the interposition of a capacitor. This capacity is arranged so that virtually the shortest distance between the two busbars is bridged. The capacity should therefore preferably still be provided in the amount of the disc 1, even if, of course, a wiring from the disc area away and back to the other busbar back to the disc area back. However, with an increase in the capacitance over the connecting path 21, a certain deterioration in the antenna characteristic can be detected.

The distance space 121 formed between the two ends 11'a and 11'b of the two busbars 11a and 11b is small in size and has a length between the two busbars, which are preferably less than five times, four times, in particular less than the three or three even equal to twice the distance between two adjacent heating conductors.

The capacitance can consist of one or more discrete or concentrated components, preferably of a capacitor 119 connected by wiring. Preferably, this can be designed as an SMD component, although a capacitance with at least two plane-parallel capacitance surfaces also arises from capacitor surfaces or foils applied parallel to the disk surface and an interposed insulator surface are conceivable. The capacitance may also consist of an electrolytic capacitor with corresponding wiring, ceramic capacitors, flexible printed circuit boards, etc. Limited to specific capacitor types or capacitor types do not exist.

The capacities in question should preferably be between 50 pF and 10 μF, in particular in a range of greater than 0.1 nF or 0.1 μF and in particular greater than 0.5 nF or greater than 0.5 μF.

Thus, if possible, the capacities should be greater than 50 pF, 0.1 nF, 0.25 nF, 0.5 nF, 1 nF or even greater than 3 nF or 5 nF or greater than 0.1 μF, 0, 25 μF, 0.5 μF, 1 μF or even greater than 3 μF or even 5 μF. On the other hand, capacitance values less than 10 μF, less than 5 μF, less than 1 μF and possibly even less than 0.5 μF make sense and are possible for certain applications.

Such a trained antenna is particularly suitable in the frequency range of, for example, 125 KHz to 1.6 GHz. In the broadcasting sector, the antenna is particularly suitable for frequency ranges from 70 MHz to 900 MHz.

Since in the embodiment shown in FIG FIG. 1 the inner heating conductors are much shorter than the outside, the outer, ie longer heating conductors would have to be designed to be increasingly thicker in order to produce comparable heating power per heat conductor.

In order to provide a compensation with respect to the length of the heating element, ie to avoid strong differences in the Heizleiterdicken is in accordance with the embodiment FIG. 2 provided that, for example, the two heating conductors lying on the inside are interconnected. In the embodiment according to FIG. 2 is so provided that the two lying to the inside heating conductors 9a and 9b adjacent to the right busbar 11b not connected to this, but are interconnected via a cross connection 9c, ie via a cross connection 9c, in the embodiment shown at a small distance parallel to the busbar 11b runs. The connection points 109 'and 109 "of these two heating conductors on the busbars 11a and 11b are provided in the embodiment shown directly on the two mutually facing ends 11'a and 11'b of the two busbars 11a and 11b, which are of different lengths in this geometry This results in a heating conductor consisting of the heating conductor 9a, the connection or the so-called connecting portion 9c and the further returning heating conductor 9b, this heating conductor as the aforementioned capacity 19 at the two closely spaced end portions 11'a and 11'b of the busbars 11a and 11b is connected.

In this case, as a further measure, whereby the antenna characteristic is improved, a further capacitor 19 'is provided, which is now connected and / or formed between the connection 9c of the two interconnected heating conductors 9a and 9b on the one hand and on the adjacent busbar 11b to the other is. Again, a concentrated or discrete component in the form of a capacitor 119 'is preferably used with corresponding connection points or corresponding wiring.

It is shown in the drawing that the additional capacity 19 ', preferably in the form of an additional capacitor 119', between the one busbar 11b and a rather middle section of the continuous heating line, the middle section 9c connecting the two heating wires 9a and 9b preferably being between 20% and 80% of the total length of the heating wire formed by the heating wires 9a, 9b and the connecting line 9c, ie in the range of one connection end calculated above 20%, in particular above 30%, 40%, 50% and of the second terminal end calculated just below 80%, in particular below 70%, 60% or 50%. In the embodiment shown, the connecting portion 9c is in a range of 40% to 50% of the total length of this heating wire formed from the heating wires 9a, 9b and the connecting portion 9c.

The illustrated example with the compound 9c can also find application for more heating and is not limited only to the two innermost heating element.

FIG. 2 also shows that, in addition to the heating field connected as an antenna field, an additional second separate antenna field 5 'with antenna conductors 105 is also provided which has, for example, a further connection 105a for connection to a downstream receiving unit (for example car radio).

Due to the specific arrangement of the antenna and heating field according to the embodiment according to FIG. 2 It can also be seen that it may be appropriate to design the busbars of different lengths so that the innermost heating conductor 9a does not have to be recirculated over a certain distance to the second busbar 11b on the right. Here are but any Modifications possible and conceivable.

It is also mentioned that, under certain circumstances, a plurality of capacitors and / or capacitors can also be connected in series on the connection path 21 between the two busbars 11a and 11b, and even taps and connections between the capacitances and body ground are possible. It is also possible, in addition to and in series with the at least one capacitance, further components, such as e.g. To switch coils on the connecting line 21 between the two busbars 11a and 11b. However, a connection between the two busbars and the interposition of capacitors via ground is excluded. The same applies to the further capacity 19 ', 119', which is provided between two interconnected heating conductors and a busbar (if necessary, several pairs of heating elements can be interconnected, so that even more capacity bridges can be provided).

As it turned out FIG. 2 results, the compound 9c is preferably aligned parallel to the adjacent busbar 11b and is there at a small distance to the busbar 11b. This distance between the connection 9c and the adjacent busbar 11b should preferably be less than 80%, in particular 60%, 45%, 20% or even less than 10% of the length of the connection 9c.

Notwithstanding the embodiment shown, the two busbars could also be provided on different, non-opposite sides of the disc 1. For example, in the further embodiment according to FIG. 3 shown busbar 11a in the area the lower limit 1b of the disc 1 is provided, whereas the second busbar 11b is arranged to extend, for example, on the right edge 1d of the disc 1 in the vertical direction. In this case, so part-circular or partially oval-shaped, curved heating conductors are provided.

Also in the embodiment according to FIG. 3 the two innermost heating conductors 9a and 9b are connected together at one end via a transverse connection 9c and their opposite heating conductor ends are connected to the two busbars 11a and 11b, the two busbars also terminating at a small distance from each other and in the free space 121, the mentioned capacitance 19 in the form of the capacitor 119 is connected on the connecting path 21 between the two busbar ends 11'a and 11'b. In the exemplary embodiment shown, the busbar 11b, which is provided predominantly on the right-hand side 1d on the disk 1 with its section 11'b, is also provided with an angled extension 111b, which again extends at the lower disk edge 1b in the immediate extension of the first busbars 11a provided there.

By the mentioned connection 9c between the two innermost heating conductors 9a and 9b, a longer heating conductor is again provided here, whereby it is achieved that the thicknesses of the heating wires do not have to vary so much from the inside to the outside due to the different lengths. The mentioned connection 9c between the two innermost heating conductors 9a and 9c is in turn also electrically connected via a further capacitance 19 'in the form of a capacitor 119' to the right busbar 11b connected.

In this embodiment as well, the outer heating conductors 9 (with the exception of the two innermost interconnected heating conductors 9a and 9b) are connected via a secondary line 15, which thus lies on the equipotential surfaces, whereby no transverse currents flow between the individual heating conductors.

Finally it will open FIG. 4 Reference is made to a slightly modified embodiment FIG. 2 shows.

In the embodiment according to FIG. 4 are also again, similar to the embodiment according to FIG. 2 , two concentrically extending part-circular heating conductors 9a and 9b connected to each other via a central portion 9c, wherein between this central portion 9c and the one busbar 11b, a capacitance 19 'is connected.

In this embodiment, between the two mentioned heating conductors 9a and 9b, two further heating conductors 9'a and 9'b are interconnected via an intermediate portion 9'c, between this intermediate portion 9'c and the aforementioned intermediate portion 9c (the other two heating conductors 9a and 9b) a capacity 19 ", preferably in the form of a capacitor 119" is additionally connected. This variant can also be provided as an alternative or in addition to the other capacities 19, 19 '. In the embodiment shown, the two intermediate sections 9c and 9'c parallel to each other and parallel to the adjacent busbar 11b extending educated. The two further heating wires 9'a and 9'b are connected to connection points 1009 'and 1009 "adjacent to the connection points 109' and 109" on the two busbars 11a and 11b.

As already mentioned, the heating and / or antenna field can also comprise other curve shapes, including, for example, trapezoidal heating conductors for the arrangement. It can also be provided more transverse to the equipotential surfaces extending secondary connecting lines. The mentioned connection lines can be designed differently. In addition, as in the beginning in FIG. 3 is shown, differently shaped additional antenna fields 105 may be provided.

In any case, can be realized by the invention, a lower frequency dependence and thus a wider bandwidth with respect to the antenna reception and improve the resonance behavior.

The embodiments have been described for the case that between the respective connection points in question, a capacity 19, 19 'or 19 "is connected, ie between the two connection points of the busbar, between a central portion of a heat conductor and a busbar or between two The respective capacitance in question can also be connected to at least one further additional component, preferably an inductance or coil, which is preferably connected in series or series with the relevant capacitance, ie in particular generating a series or series In particular on the connection route 21 Thus, therefore, a capacitance and an inductance or a coil can be connected directly in series.

Claims (23)

1. Antenna panel for a motor-vehicle window, in particular a rear window, having the following features:

   - at least one heating panel (7) having a plurality of conductors (9) is provided,

   - the conductors (9) that form the at least one heating panel (7) are provided between at least two bus bars (11 a, 11 b) running inside or on a window (1), preferably in an equidistant arrangement,

   - the heating panel (7) is entirely or partially connected as an antenna panel (5), and/or at least one separate antenna panel (5') on the window having at least one antenna conductor (105) is provided at least in addition to the heating panel (7),

   - all of the bus bars (11 a, 11 b) are provided on one side of the window (1) or on two sides of the window (1) that are not opposite each other,
   characterised by the following additional features:

   - at least one capacitance (19') is connected in a direct connection between one of the at least two bus bars (11 a, 11b) and at least one central section (9c), formed between 20% and 80% of the total length of a heating wire (9; 9a, 9b, 9c), of the heating wire (9a, 9b, 9c), and

   - the at least one capacitance (19') is greater than 50 pF.
2. Antenna panel according to claim 1, characterised in that at least one capacitance (19") is connected between at least two central sections (9c, 9c'), formed between 20% and 80% of the total length of two heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c), of the heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c).
3. Antenna panel according to claim 2, characterised in that the at least one capacitance (19") is connected in a direct connection between the associated connection points on the two central sections (9c, 9'c) of the heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c).
4. Antenna panel according to any one of claims 1 to 3, characterised in that at least one capacitance (19) is connected between the at least two bus bars (11a, 11b).
5. Antenna panel according to any one of claims 1 to 3, characterised in that the at least one capacitance (19') is connected in a direct connection between the associated connection point on the bus bar (11 a, 11 b) and the relevant central section (9c) of the associated heating wire.
6. Antenna panel according to any one of claims 1 to 5, characterised in that the at least one capacitance (19, 19', 19") is composed of a discrete component, i.e. a capacitor (119, 119').
7. Antenna panel according to claim 6, characterised in that the capacitance (19, 19', 19") is composed of an electrolytic capacitor, a ceramic capacitor, a surface mount device (SMD) or of insulated conductor tracks arranged parallel to the window plane in layers one on top of the other, or comprises these.
8. Antenna panel according to any one of claims 1 to 7, characterised in that the capacitance (19, 19', 19") is greater than 50 pF and less than 10 µF, in particular is greater than 50 pF, 0.1 nF, 0.25 nF, 0.5 nF, 1 nF, 3 nF, 5 nF, 0.1 µF, 0.25 µF, 0.5 µF, 1 µF or even is greater than 3 µF or greater than 5 µF, and that the capacitance (19', 19") is preferably less than 5 µF, 1 µF and in particular less than 0.5 µF.
9. Antenna panel according to any one of claims 1 to 8, characterised in that at least another one further component is connected in series with the at least one capacitance (19, 19', 19"), in particular an inductor or an inductance forming a series resonant circuit.
10. Antenna panel according to any one of claims 1 to 9, characterised in that two heating conductors (9a, 9b; 9'a, 9'b) are provided, which at least over some of their length run adjacent and in particular equidistant to each other, and which are connected together via a connecting section (9c; 9'c) at their one end region, extending their total heating-conductor length, whereas the respective opposite ends of the two heating conductors (9a, 9b; 9'a, 9'b) are each connected to one of the two bus bars (11 a, 11 b).
11. Antenna panel according to claim 10, characterised in that the connecting section (9c; 9'c) runs parallel to an adjacent bus bar (11 a, 11 b) and/or that the two connecting sections (9c; 9'c) run parallel to each other.
12. Antenna panel according to claim 10 or 11, characterised in that two pairs each comprising two heating conductors (9a, 9b; 9'a, 9'b) are provided, which at least over some of their length run adjacent and in particular equidistant to each other, and which are connected together in each case via a connecting section (9c; 9'c) at their one end region, extending their total heating-conductor length, whereas the opposite ends of the respective two pairs of heating conductors (9a, 9b; 9'a, 9'b) are each connected to one of the two bus bars (11 a, 11 b), and in that the two connecting sections (9c; 9'c) are connected by the at least one capacitance (19").
13. Antenna panel according to claim 11 or 12, characterised in that the two pairs each comprising two heating conductors (9a, 9b; 9'a, 9'b), including their respective associated connecting sections (9c; 9'c), are electrically connected only at their ends to the respective bus bar (11 a, 11 b) and with their associated connecting section (9c; 9'c) only to the at least one capacitance (19').
14. Antenna panel according to any one of claims 10 to 13, characterised in that the one pair of heating conductors (9'a, 9'b), including the associated connecting section (9'c), lies physically between the two connected-together additional heating conductors (9a, 9b), including the associated connecting section (9c).
15. Antenna panel according to any one of claims 10 to 14, characterised in that the connecting section (9c; 9'c) is at a distance from the adjacent bus bar (11 a, 11 b) that is less than the length of the connecting section (9c), preferably that is less than 80%, 60%, 40%, 20% or even less than 10% of the length of the connecting section (9c).
16. Antenna panel according to any one of claims 1 to 15, characterised in that the adjacent ends (11'a, 11'b) of the at least two bus bars (11a, 11b) lie at a short distance apart, where the gap (121) is equal to less than five times, preferably less than four times, less than three times or less than twice the distance between two adjacent heating conductors (9; 9a, 9b).
17. Antenna panel according to claim 16, characterised in that the gap (121) between the first and second bus bar (11 a, 11 b) is provided so that one of two adjacent heating wires (9; 9a, 9b) connected together via the connection (9c) is connected to the end (11'a) of the first bus bar (11a), and the other heating wire (9; 9b) is connected to the end (11'b) of at least one further bus bar (11 b).
18. Antenna panel according to any of claims 1 to 17, characterised in that the two bus bars (11a, 11b) are provided on or inside the window (1) symmetrically about a plane of symmetry (14) running vertically.
19. Antenna panel according to any one of claims 1 to 18, characterised in that the at least two bus bars (11 a, 11 b) are arranged on the same side of the window (1), preferably on the lower edge region adjacent to the lower limit (1 b) of the window (1).
20. Antenna panel according to any one of claims 1 to 19, characterised in that a bus bar (11) is provided adjacent to the left-hand or right-hand limit (1c, 1d).
21. Antenna panel according to any one of claims 1 to 20, characterised in that at least one bus bar (11 a, 11 b) comprises sections oriented in two angles with respect to each other, where one section (111 b) is arranged on one side (1 b) of the window (1) and the other section (111'b) is arranged on another adjacent side (1d) of the window (1).
22. Antenna panel according to claim 21, characterised in that the one section (111 b) of the bus bar (11b) is arranged on the same side (1b) of the window (1) on which the first bus bar (11a) is also arranged.
23. Antenna panel according to any one of claims 1 to 22, characterised in that at least one secondary conductor (15) is provided, via which at least some of the heating conductors (9) are connected across equipotential surfaces.

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